


Psychogenic

by perishSong



Category: Haikyuu!!
Genre: Masturbation, Other
Language: English
Status: Completed
Published: 2015-03-23
Updated: 2015-03-23
Packaged: 2018-03-19 04:50:12
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 393
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3596976
Author URL: https://archiveofourown.org/users/perishSong/pseuds/perishSong
Summary: <blockquote class="userstuff">
              <p>I was studying erectile dysfunction and wondered if it would help me write smut.</p>
<p>It surely didn't.</p>
            </blockquote>





	Psychogenic

You know how psychogenic erections work, erotic stimuli releasing neurotransmitters such as dopamine and oxytocin. Ushijima’s mind is filled with images, slender fingers curl around his shaft, still on his flacid phase, incoming blood stream still lower than the outcoming. It doesn't take long though for his parasympathetic division of the autonomic nervous system start working, the branches coming right from his sacral plexus, a stream of acetylcholine releasing nitric oxide right from his endothelial cells, causing immediate vasodilation through the activation of the guanylyl cyclase which, in turn, transforms guanosine triphosphate in cyclic adenosine monophosphate. 

The extra blood fills his corpora spongiosum and cavernosa, the tumescent phase coming quick with this rapid raise of his intracavernous pressure making his shaft pulse in time with the beats of his heart, which were, by the action of norepinephrine, racing. Ah, his sympathetic division, darkening Ushijima’s eyes through mydriasis, his breathing coming out as pants, but still maintaining his oxygen saturation. His hands move fast, precum acting like natural lubrication.  
He leans his head back, erratic words escaping his lips, active locus coeruleus working as if an intake of narcotics filled those cells. On rigid erection phase the blood stream is completely ceased, from now on his climax builds up almost painfully.

The emission phase starts, spermatozoa in a mixture with products that were once secreted by the accessory sexual glands are ejected right into the posterior urethra by sequential epithelial secretion and continued contractions from his smooth muscle cells. Beads of sweat forming all over his forehead as expulsion phase starts, sperm now ejected from the urethra through the glans meatus. The smooth muscle fibers of the bladder neck contract, this way making it impossible a backward flow of semen into the bladder and consequent cystitis. The pelvic floor muscles, working in rhythm with the bulbospongiosus and ischiocavernosus muscles, displaying stereotypical rhythmic contractions to propel semen, the external urinary sphincter opening up to allow the spurt paint his fingers and stomach white with proteic fluid.

With that his erection subdues, parasympathetic stimulation discontinued, a baseline stimulation of the sympathetic division causes his arteries to contract forcing the blood out of the erectile tissue, length and thickness diminishing by the time.

The release of prolactin, oxytocin and vasopressin demands for a recovery time, inducing a known dizziness and soon he’s on the embrace of sleep.

**Author's Note:**

> I'm sorry everyone.


End file.
